Block-designed hydrogel with segregated CNTs/MXene networks and PEDOT interfacial engineering for neuro-skin applications: Multimodal sensing, nerve regeneration and self-powered energy harvesting

Conductive hydrogels typically encounter intrinsic trade-offs among sensitivity, mechanical robustness, and multifunctional integration. In this study, a block-structured hydrogel addresses these limitations by spatially segregating one-dimensional (1D) carbon nanotubes (CNTs) and two-dimensional (2D) MXene within a semi-interpenetrating polyacrylamide/sodium alginate (PAM/SA) network. To further enhance interfacial conductivity, MXene-rich regions are coated with poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS), achieving a conductivity of 16.2 S m −1 . This bioinspired structure realizes strain-dependent and strain-independent conductive pathways while suppressing phase separation, enabling ultrahigh sensitivity (gauge factor = 36.6 at 600–800 % strain) and wide pressure detection (0.1–21.7 kPa). This multifunctional hydrogel-based sensor features motion monitoring, temperature sensing, and Morse code encryption capabilities. The hydrogel mitigates the stress-masking effect through a biomimetic modulus design and, in synergy with the SA/MXene components, effectively reduces inflammatory factor levels. Simultaneously, the three-dimensional conductive network enhances electrical signal transmission, facilitating the functional recovery of neural tissues and promoting sciatic nerve regeneration in mice. Furthermore, the integrated friction-based nanogenerator demonstrates efficient energy harvesting capabilities, achieving a peak power density of 3.2 W m −2 . By seamlessly integrating sensing, nerve regeneration, and energy autonomy, this conductive hydrogel establishes a pioneering “neuroskin” platform, enabling a closed-loop “sense-repair-power” interface for next-generation bioelectronic systems.